1 Scope
This document specifies the terms and definitions, general requirements, monitoring requirements, monitoring software, signal processing and feature extraction parameter alarms and analysis diagnostic monitoring and analysis reports for reciprocating piston compressor monitoring systems (hereinafter referred to as monitoring systems).
This document applies to the monitoring system for reciprocating piston compressors.
2 Normative reference documents
The contents of the following documents constitute essential provisions of this document by means of normative references in the text. Among them, the date of the reference documents, only the date of the corresponding version applies to this document; do not note the date of the reference documents, the latest version (including all the revision of the list) applies to this document.
GB 3836.1 Explosive atmospheres Part 1: General requirements for equipment
GB/T 20921 Glossary of machine condition monitoring and diagnosis
3 Terms and definitions
The terms defined by GB/T 20921 and the following terms and definitions apply to this document.
3.1
Reciprocating piston compressor monitoring
Through data acquisition equipment, the reciprocating compressor key phase, vibration, offset, temperature, pressure and other signals are collected online or offline, and after a series of data processing such as filtering, amplification, feature extraction, etc., the operating state characteristics of the reciprocating compressor parameters are obtained and stored in the data processing and storage equipment to achieve the monitoring and analysis of the operating state of the reciprocating compressor.
3.2
The whole eycle data acquisition
The data acquisition is carried out in accordance with the cyclic operation of the reciprocating piston compressor. The length of the data corresponds to one or more operating cycles of the reciprocating piston compressor.
3.3
Key phase monitoring
The crank angle of the reciprocating piston compressor is monitored by means of a metal block or key phase groove on the crankshaft or flywheel of the reciprocating piston compressor and the reference orientation signal of the piston position of each cylinder.
3.4
Synchronous data acquisition of all channels
Synchronous data acquisition of all channels of a single or multiple data acquisition device in accordance with a unified command.
3.5
Continuous data acquisition
Continuous data acquisition according to a certain sampling rate for monitoring the vibration, offset, speed and other signals of the continuous working cycle of a reciprocating piston press.
3.6
Interval data acquisition
Data acquisition is carried out according to a certain sampling rate and a fixed interval time to achieve single or multiple working cycles of the reciprocating piston compressor during the interval time. Monitoring of signals such as rotational speed.
3.7
Piston rod displacement deviation monitoring
Piston rod displacement deviation monitring
An eddy current sensor is installed in a direction perpendicular to the central axis of the piston rod to monitor the displacement signal during the movement of the piston rod.
3.8
Piston rod axes orbit monitoring
By means of eddy current sensors for monitoring the offset of the piston rod, the offset signals are monitored in two directions perpendicular to the central axis of the piston rod and at an angle of 90°, and the trajectory of the geometric centre of the piston rod in several cross-sections is calculated.
The vibration signal of the outer casing of the cylinder is monitored by an acceleration sensor in the axial, horizontal and vertical radial directions.
4 General requirements
4.1 In addition to the equipment and measurement methods specified in this document, the use of other equipment and measurement methods of equal or greater accuracy is not excluded. All tests that affect the acquisition of signals. Measuring and processing equipment and devices shall be calibrated periodically or prior to use against equipment that has been calibrated to the appropriate national standards.
4.2 Monitoring systems may be selected but are not limited to key phase, crosshead slide housing vibration. Crankcase vibration, piston rod deflection. Intake valve cavity temperature, exhaust valve cavity humidity, cylinder vibration, cylinder dynamic pressure, intake and exhaust temperature, intake and exhaust pressure and other signal monitoring.
4.3 All types of sensors should be safe, accurate and reliable, and their installation should not adversely affect the normal operation of the unit.
4.4 The selection and installation of all electrical equipment, instruments, components and materials shall apply to the specified electrical hazardous location classification and comply with the requirements of GB 3836.1.
4.5 The signal circuit between the sensor and the data acquisition equipment should be correctly and reliably connected, and the signal circuit commissioning and general judgement of the data should be referred to in Appendix A.
4.6 Data acquisition equipment should have third-party accuracy and reliability test certification materials, including but not limited to high and low temperature working test high and low temperature storage test. Electromagnetic compatibility test, reliability test, vibration test, etc.
4.7 The monitoring system shall meet with the DCS system ERP system, gas volume stepless adjustment system . Equipment management platform for state control signals and monitoring data interaction needs, at the same time should not cause adverse effects on the normal operation of the above systems.
5 Monitoring requirements
5.1 Layout of sensor measurement points
5.1.1 The configuration, installation and layout of the sensor measurement points of the monitoring system can be found in Appendix B and Appendix C.
5.1.2 The number of sensor measurement points depends on the size of the unit, the mechanical structure and the number of cylinders and valves, and should be configured reasonably and effectively according to the structural characteristics and characteristics of the reciprocating piston compressor.
5.1.3 The monitoring category, sensor installation position sensor selection, signal acquisition mode and whether the alarm is appropriate according to the provisions of Table 1.
5.2 Sensor installation requirements
5.2.1 paste, magnetic adsorption, thread fixing welding and other installation methods should ensure the strength and reliability of the sensor and other equipment installation, should not occur off, loosening and other failures.
5.2.2 The installation of the monitoring sensor shall not affect the support rigidity of the unit and the sealing of the high pressure gas.
5.2.3 The installation position of the monitoring sensor shall be reasonably selected according to the structure of the unit, monitoring needs and user requirements.
5.2.4 For units with horizontal cylinder layout, the installation angle of the live distress rod offset sensor should include two directions: vertical and horizontal; for units with vertical cylinder layout, the installation angle of the piston rod offset sensor should include two directions perpendicular to the axis of the piston rod and with an angle of 90".
6 Monitoring software
6.1 Monitoring software shall include but not limited to data acquisition software, data communication software. Data management software. Fault alarm software. Data analysis and diagnosis software database software.
6.2 The monitoring software shall have a complete data communication interface function and can communicate with the DCS system, ERP system, gas volume stepless adjustment system, equipment management platform for data communication.
6.3 The monitoring software should be able to configure the measurement point configuration, configure and set the measurement point name, measurement point position number. Measurement point sampling rate, measurement point sampling points, measurement point sensor type, measurement point installation location, channel filtering parameters, alarm threshold value, and allow modification.
6.4 The monitoring software should support continuous data acquisition and interval data acquisition mode, and can modify the data acquisition mode to ensure that the refresh rate of each group of real-time data does not exceed 5 s. For fast-changing transient fault signals, continuous whole-cycle data acquisition and storage of all measurement points can be carried out automatically.
6.5 The monitoring software should be able to match database information according to the specific configuration of the measurement points, and to choose whether to carry out alarms and store data.
6.6 The monitoring software should be able to modify the alarm mode of each measurement point, including but not limited to over-the-line alarm, slow-change trend alarm, fast-change trend alarm; it should have a variety of alarm display methods such as sound and light alarm, SMS alarm and email alarm; it should have the ability to optimize the alarm strategy when the data repeatedly crosses the alarm line and not to repeat the alarm.
6.7 The visual analysis and diagnosis function of the monitoring software should be in accordance with the provisions of Table 3.
7 Signal processing and feature extraction
7.1 The monitoring system should be based on the key signal, complete crosshead slide housing vibration. Crankcase vibration, piston rod deflection, cylinder vibration, cylinder dynamic pressure and other signal processing and feature extraction.
7.2 The acceleration vibration signals such as crosshead slide housing vibration and cylinder vibration shall be extracted from the whole cycle acceleration vibration peak, crank rotation angle 0°~360° segment acceleration vibration peak. Frequency characteristics and other parameters.
7.3 The crankcase vibration measurement point signal should be extracted from the whole cycle of vibration velocity RMS frequency characteristics and other parameters.
7.4 The piston rod offset measurement point signal should extract the average value of the whole cycle piston rod offset, the peak value of the whole cycle offset, the peak value of the segmental offset of the crank angle 0°~360°, the characteristics of the face rate and other parameters.
7.5 The cylinder dynamic pressure measurement point signal should be extracted from the pressure average, pressure maximum, pressure change rate and other parameters.
7.6 Signal acquisition and processing mode in the normal state can be used interval data acquisition, in the case of fault and alarm should be used continuous whole cycle data acquisition, and to achieve the unit monitoring data automatically encrypted storage.
7.7 The calculation methods of the above-mentioned characteristic parameters can be referred to GB/T 19873.1, GB/T 19873.2, GB/T 23714 and GB/T 25742.1, and the calculation methods of the key characteristic parameters can be found in Appendix D.
8 Parameter alarms and analysis and diagnosis
8.1 Alarm values for the various monitoring parameters are generally set according to national standards or recommended limits by the compressor manufacturer.
8.2 If there is no corresponding national standard or compressor manufacturer's recommended limit value for the monitoring parameter, it can be set according to the historical normal and fault operation data of the unit, i.e. set the corresponding magnification Y according to the size of different parameter characteristic values in the fault state of the unit, and take the size of different parameter characteristic values in the normal state of the unit multiplied by Y as the alarm limit value of this monitoring parameter characteristic value. The magnification factor Y shall be selected according to the operating load of the unit by means of data self-learning or manual setting.
8.3 The time, frequency and angular signal characteristics of the monitored parameters of the reciprocating piston compressor shall be analysed by means of various analysis plots in the online monitoring software, and the analysis and diagnosis shall be carried out against the fault mechanism and the change in fault characteristics.
8.4 The analysis and diagnosis process can be completed manually or through the automatic diagnosis function of the fault drop, and the automatic diagnosis results can provide reference for the manual analysis and diagnosis.
8.5 The fault analysis and diagnosis process can be referred to GB/T 22393, GB/T 22394.1 and GB/T 23713.1. See Appendix E for the correspondence between common faults and characteristics.
9 Monitoring and analysis report
9.1 Monitoring and analysis reports can be generated automatically by the monitoring software or written manually by guanxi.
Appendix A (informative) Normal range of monitoring signals
Appendix B (informative) Common sensor point configurations
Appendix C (informative) Commonly used sensor point installation layout options
Appendix D (Informative) Calculation method for monitoring characteristic parameters
Appendix E (informative) Comparison table of common fault monitoring characteristics
Appendix F (Informative) Monitoring Analysis Report Template
References
Foreword
1 Scope
2 Normative reference documents
3 Terms and definitions
4 General requirements
5 Monitoring requirements
6 Monitoring software
7 Signal processing and feature extraction
8 Parameter alarms and analysis and diagnosis
9 Monitoring and analysis report
Appendix A (informative) Normal range of monitoring signals
Appendix B (informative) Common sensor point configurations
Appendix C (informative) Commonly used sensor point installation layout options
Appendix D (Informative) Calculation method for monitoring characteristic parameters
Appendix E (informative) Comparison table of common fault monitoring characteristics
Appendix F (Informative) Monitoring Analysis Report Template
References
